It hasn't taken long for the New Orleans Saints to put last year behind them. Coach Sean Payton is back on the sidelines. QB Drew Brees looks in total control on the field. And most remarkable of all, the defense is dominating.

That's right -- a defense that finished dead last in all our rankings in 2012 is now the NFL's sixth-ranked D three weeks into the season. So with a roster featuring a number of the guys who struggled so much last year, what's caused the turnaround?

To read more on the Saints' upgraded D and see the rest of Pro Football Focus' evaluation of Week 3, sign up for Insider today.